Inheritance patterns of flower colour in garden pea plant and snap dragon differ. Why is the difference observed? Explain the difference with the help of crosses in their inheritance patterns.

Explanation

Inheritance pattern of flower colour in Pisum sativum (garden pea) follows law of dominance that is out of the two alleles of the flower colour (gene) the dominant allele is expressed (phenotypically) and the recessive allele is suppressed when both are present together in heterozygous condition. The recessive trait is expressed only when the recessive allele is present in homozygous condition
In case of Antirrhinum (snap dragon) the flower colour shows incomplete dominance and all the F1 progeny is of pink colour It is because the allele for red colour is not completely dominant over its recessive allele. The law of dominance is not exhibited in this case.